There is no established scientific method called "s and p time method". It's possible you're referring to a specific concept or technique used in a particular field, but without more context, it's difficult to tell.

To help me understand what you're looking for, could you please provide more information? For example:

* What field of science are you interested in? (e.g., biology, chemistry, physics, etc.)

* Where did you encounter this term? (e.g., a textbook, a lecture, a research paper)

* Do you have any other details about the method? (e.g., what it's supposed to do, what it involves)

Once I have more information, I can help you understand the method you're asking about.